With the popularity of electronic devices, people use and control the electronic device to help with work, study, and entertainment almost every day. Enabling a user to conveniently and quickly control an electronic device has been a long-pursed goal of manufacturers of electronic devices.
A wearable device (such as a smart watch, smart gloves, and smart accessories) among electronic devices usually has characteristics such as being attached to users, compact, and low energy consumption. These characteristics result in that most of wearable devices have a small input area and low input capability.